PARP1 and small cell lung carcinoma: In a similar manner, a combination of I-BET762 and Olaparib, the remaining tested PARP inhibitor, showed higher cytotoxicity in H2171, H446, Lu135, and H345 SCLC cells when compared to single agents, confirming the additive effect by I-BET762 with PARP inhibition (Figures S2 and S3).